Gas-engine muffler



Feb. 12 1924. v v

F. KOPPER, JR

GAS ENGINE MUFFLER Filed Nov 25 1919 3 Sheets-5heet 1 Feb. 12 1924.

F. KOPPER, JR

GAS ENGINE MUFFLER Filed Nov. 25; 1919 V Emma "fade/1% flay 05 W I l Feb. 12 1924. 1,483,354

F. KOPPER, JR

ms ENGINE MUFFLER Filed Nov. 25, 1919 s sheets-shears Subawtoz g I I I FrZdw'zwfipperfi,

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Piltent ecl Feb. 12, 19 24.

FREDERICK 36mm, an, "m? W'Afil PATENT GEYFKQE.

ERIE

NGTON, STEEL??? 639.31%

\ GAS-CENGII HE MESFFLERQ Application filad Kwember To all whom '53 may @Mmern: I

Ba it known that I, FREDERICK Kflmwn, J12, 2'2, citizen of the United States OLE-Amerim, residing at Naslxlnglzon, in the District; of Columblm, l'mve'invcmliml certain new" a, 'ussa'ful Improve'r ants ls: Gasfilngim filers, of which the :Eollmmng is a spam-1.. cation.

This invention rclszies 21a imprmwemenis 1:5 gas-engine muflling devices and more particularly to combimad 'mullleir and Emilie? cut-out.

One object; m? this invention is to provide a simple, and efilrient device by means which the mufliiug of the noise of the 42-20 plosion may be acmmplished with the Em r mat-ion of a negligible baclvpressm'e in. this exhaust; pi ef A seccnu abject is $0 provide an elfi siev mufiiing device which may be 8ljllStil t0 different types of 1110?.01'5 accomplishing gt-uz'pese uquaily WQll under the xelmngecl conditions and w'hlch may justed for use with film same mate; {'0

vide a greater or less mufiling ull'ect,

Anotlwr object is to produce a mufilar in which the formation of a 9artial vacuum 01 back-pressure in due exhaust pipe be nearly completely eliminated, or, in any iwfillll, reduced to a point where the effec; is of li tle Qonseq'uence.

.A further object (If the inventien provision of a muffler wherein the 111111? 5 effect is aniiomalilfall p walled by and 1; accordance with the speed of the mate? L0 whiah it mpi-zmtively CUHHOQtQfi.

It, will. umlerstnsd {hi ill?- V of znufiiers now Im 'wuiely in 1192s., the

pmvidml. an. expa mm pnaanlyer loam 0!? near the end 9f the e "must, pipe a 1110x012 "Elbe lntmiioz. of {15315 @llam es 0i vanes m: mllle plates; r kind the object in *JlQW EGG-U355 12 l the burni; gases 'mssing from the xlnmmh under i2 rfilutively high prussmre, t0 CifiliSQ them to expand in the chamber and 0 low up their lisq-l'sarge inlo the atmo ph' ra by the system of vanes Such an. arrangement *1: this is ml ill! be c f com the noise of the Mp1 are checked 'wltlzin. Qt tl'm backpmwaure which in farm. ficiency 0f the mm'or sinza it of the power of like (angina lessm A further Ills" zdi 'zmfiage in a mu 2? of this type is that 1t in D6 sense mtales- 11m can it nmu s0 same by unions sfla 0f sham? 1391f, em which t0 pzvviiling mufi fi ers 0f a different pa size ch 035 engine. L. geintt, 01"" (Ill:

gust l; I resglt Ehat the, greater the engine apeedl, mm 11 s mcreasmlfame of r;"y pnlosimn izhe greater i5 the-back-pressure pi'cducei Such mufilers, a519, rule, are equipped. a de' vice known a cut-cut t0 :bae'iz {he 'csmlipiy a cmwenient flux-"1 and this fill-out "s means far lsy' passing the films milling; the Klmust div 1 l the ammsplw "without he bafilss dam 1 L'Wkfflll;

L M cutout 1S, son- Further, it is so designed as to proauc'e any (lQS'lYQu clfigree of215:1.1filing or it nmy be adjustecl to give. "aha ffect a cubeut.

Flip the devlae has 1 0 labamla system .psazwien shamber, to @511 $11 101; and the Sim-- cl v' film; with its efax zumm trclki clssm L, l.

0;" dear may mint mounting,

a mflmusb but showing elements oi a.

It will be understood that the. ordinary gas engine explosions leave the exhaust pipe 0 )ening, it unmullled, in distinct pulls.

hese putts or condensations are -followed by corresponding rarefactions and the waves so formed produce the auditory effects. In the ordinary muiller, the slowing up of the gases in conjunction with the expansion chamber tends to eliminate the differences in pressure and to reduce the noise.

But in the present invention, the spring dooraccomplishes th me purpose. The door rides upon the waves of the explosions and is forced outwardly by successive condensations. spring to the movement of the door is Sullicient to tend to cause e ualization of pressure; that is to say, the condensations are checked and merge with the rarofactions. This equalization in pressure damps the amplitude of the waves, resulting in a reduction in sound.

Since the successive rarefactions tend to produce a partial vacuum which is effective in setting up back-pressure, it will be obvious that the present invention, in eliminating this variation in pressure, not only mullles the sound, but also prevents backpressure, which would absorb power from the engine.

It will be seen that the device as briefly described is simple and inexpensiye in coir struction and without parts that wear out easily. Adjustments, as will be later described, are easily and readily made.

For a better understanding of the device, references is now made to the accompanying drawings showing the preferred and various modified, forms of the device.

In the drawings Figure l is a perspective view of the de vice.

Fig. 2 is a perspective .view, showing the mufiling element embled.

Fig. 3 is a ry sectional view, taken on line 3 4 Fig. 4 is a view in tran on the line -l-- in 1 Figs. and G are iev similar to Fig. 3, slightly modified form. r

Fig. 7 is a view a pair of muiiling elemcii tion.

Fig. 8 is a 88 of Fig. 7.

Figs. 9, 10, 11, 12 and iii are views showin the i1 vention in root ed torms.

n the various views in which like 18f6T ence characters refer to like parts, the exhaust pipe 1 ot the motor is provided at its end with a chamber 2 of slightly increased diameter. It has been found that the provision at this point of a chamber of slightly to showing in operative posisectional view taken on line increased diameter improves the mufiling The resistance offered by the' 7 held yieldingl .ing to compr s effect permitting expansion of the gases. Leading from the chamber there is an ension 3, o -shaped in cross section, and pro.- viding the main body oi" the mullling device proper. Mounted by means of a bin e 4 on the open side of the U, there is a oor or gate 5 provided with a pair of cranks 6 and 7, The hinge, as will be seen, is of usual form and has a portion 8 overlying: the hinge pin 9, of which the cranks 6 and 7 form the end portions. The overlying member 8 is bolted to the body of the 'U- shaped portion of extension 3, as shown at 10. Any convenient way of mounting the ate 5 is permissible, provided it has free om of movement within the trough of" member 3.

The gate 5 conforms closely to the insid dimension of the U, but is allowed entire freedom of movement on its hinge, except as will be now explained. The crank 7 pro jects downwardly from the hinge pin and at its lower extremity engages a coiled spring 11, mounted longitudinally of the member 3 in a spring frame 12. The frame 12 isattached to the side of the U by means of a pair of bolts 13, the shanks of which roject through a slot 14 in the frame 19.

t will be seen that b this arrangement the frame may be move to different positions along member 3.

The engagement of the crank T with the spring 11 results in-the door being held yieldingly in any desired position with reference to the member 3. As will be seen.

if the spring frame is moved to the left in Fig. 1, this draws the crank 7 with it,

and the door 5 will move downwardly until it strikes the lower surface of the U. This,

the prifice of'the Moving the spring makes it possible to desired angle to the gases and to change tr e t to which the exhaust orifice closed, lire door 5 being in any position in which it exhaust gases inength, they would "her opr i, crank 7 tendoortion of the spring (Fig. l) to J or it and. to extend the portion to the It will be understood that the force of the exhaust gases does not come regularly, but in explosive pufis. Consequently, some provision is necessary to prevent the door from havin too great a freedom of movement in eit or direction, and the location of the point of engagement of the crank T with the spring, midway the expansion chamber 2. frame 12 to the right place the door 5 at any the outcoming may be set. i. l crease in volume and 5 force the door '5 Ill ends thereof, attains this result. The door,

By the adjustable mounting of the spring, as shown, it is possible to control the degree of muilling. As previously explained the extent to which the noises of the explosions of the motor are muiiled depends upon the extent of the interoosition of the door 5 in the path of the exhaust gases. By adjusting the door 5 to a position as shown in Fig. 1, a very complete muflling result is possible. But should less mufiling be desired with less resistance to the passage of the exhaust gases into the atmosphere, this may be accomplished by setting the door in a position such that an orifice of increased size is presented. It will be understood that the position of the door is to be. varied. in accordance not only with the .w ree of mufiling desired, but; also W: h reference to the motor to which the do is attached. An 8 or 19 cylinder motor .l, of com I produce a' greater volume of exhaust gases than a 4 cylinder motor, and consequently, for a motor of a larger number of cylinders, door 5 must be set in a position to provide a less restricted outlet for the gases.

. Should it be desired, for any reason, to out out the mufiler completely, this is provided for by having a crank 6 attached to the door, as shown. To the crank 6 there to be attached a cord or chain to run to the drivers seat or to 211 suitable pedal. and. the

door 5 may be held wide open for such periods as me" be desired. Under these coir so n'milling i ditious there 1:

\Vhile the form shown in Figs. 1, i5 and is the simplest and preferred type, it has been found. that beneficial results are ob tained by making slight changes in the form of the door 5. door in which the outer extremity indicated 'at 15 has been bent slightly so that the-door may have a larger surface of contact with the lower surface of the U. This prevents,

any possibility of clrattering when the door to, he held nearly closed to produce an extreme mullling effect. In the modification shown in'l ig. 6 the door 5 is bent in curved lorinfand the lower surface of the U of member is j llflvld fl with 7 downwardly curved lip 18. with which the o iter extremity 3.7 of the door, bent oownwardly as shown, some in contact. The elfect of this cominaticm of curved parts is to pro duce a greater'muliling effect. This would necessarily be the case. since the path of the gases is slightly changed in leaving the mufiler, and in making this change in direction, the gases come into closer contact with the door 5. In. Fig. 7 there is provided, as shown, a pair of doors 5, 5, hinged atop posit-e on the member 3, 1 pair of cranks "'2'. l". cnga At their outer extreuiiit. of the doors arehent, large contact :%surface.

In Fig. 5 there is shown a ment as this, While slightly more complex than. the. simplest form, increases the mullling effect. It is necessary to provide only one of the doors 5 with the crank 6 for use as cutout. Fig. 8 shows a cross sectional View of the device in Fig. 7 and indi ates how the pair of cranks 7, 7, engi :he spring 11.

In Fig. there is shown a series of inuliling devices placed one after the other and working independently. Such an arrangement provides a satisfactory mufller for engines of extreme high power, as for instance. aircraft engines, and the muflling effect is cumulative. The doors 5* 5", 5' and 5 may he set to produce a cumulative nmilling eiifcct.

In the modification illustrated in Fig. 10, the door or closure 5, is formed of a piece of metal having an inherent resiliency. The

door is secured at its upper end to the extension 3, and thence tapers or extends downwardly to a point closely adjacent the outer end of the floor of the member 3. Obviously the force of the outcommg gases will cause the lower end of the door 5 to wardly tapered, or flattened and outwardly flared. This construction is beneficial in that it permits of additional ex ansion of the gases, immediately prior to t eir exit. It will be seen that the novel device provides a muilier which depends for its proper functioning upon the interpositionofthe' door 5 at an angle in the path of the gases, and. as previously explained, this ser es the poso of tending to equalize the cor densa- "ons and rare'lactions in the exhaust By v i m of the fact that the door has relatively t :iizreugth, making an acute angle wit the lower surface of the!) member 3 the friction set up and the extent to which the are slowed. up in their. passage to the.

atmosphere is com iaratively small. While it has been found n'rullier will give practically the same mulliing ellccias the type at present in use, there is a lessening in back-pressure of be two i Gil and.

. to be on stood that while the viewB in the drawings disclose the perferredforms of the invention, the novel device is obviousy actual tests that this closure.

2. A mufiier provided with member ing an orifice, a closure pirotuil. mo..-uicd to restrict or enlarge said orifice, a flexible element in alignment with said member and connected to said closure and adopted. to yieldingly limit the swing thereof, and means for bodily moving said element to vary the normal position 05 said closure.

3.13. niul'liler provided with a member having an orifice, a closure pivotully mounted to restrict or enlarge said orifice, a re silicnt element mounted in parallel with said member, and connected, I ends, to said closure, whereby to d closure in at predetermined pus-non with respect to said orifice, and means 501 bodily moving said element to r. diiicrcnt position, to vary the normal position of closure, substantially as described.

4. A mutiler provided with a. member having an orifice, a closure morubl positioned to restrict the size of said. orifice, resilient means connected to the closure and normally tending to hold it in a predetermined posi tion, a support for said resilient menus, and means for adjusting the position ol seid support whereby the closure may assume another position.

A mufiler provided with tl'llltllllkl having an orifice, a closure curried by said member and moveblv positioned. to restrict the size of said orifice, c. Clr. to the closure, :1 spring i'r: mounted on said member, and u. spr in said frame and in engagement with crank to yieldingly retain closure position.

6. A inufller provided with c ing on orifice, :1 closure nu member and adapted. for movement ni o position to restrict or enlarge said orifice, resilient means in engugmcnt with said closure and yieldingly re ting movement thereof in cithcr'direction, and means for adjusting the amount of resistance of said resilient means. I

7. A niufiler provided with a. member having an orifice, a closure pivotally mounted to restrict ,or enlarge said orifice, in combination with a flexible element fixed at points longitudinally of itslength, and means connecting said closure to said ele ment, intermediate said points, whereby to normally hold said closure in a predetern-ined position.

8. A mufiler provided with a member having an orifice, :1 closure pii'otully mounted to restrict or enlarge said orifice, in combination with u flexible element fixed at points longitudinally of its length, means connecting said closure to said element, intermediate suid points, whereby to normally hold said closure in a predetermined position and means permitting bodily moving said clement with respect to said closure, whereby to normally hold suid closure in another predctern'iined position.

t). A mull'ler provided with a member having an orifice, n closure mounted on said member and movableto restrict or enlarge suid orifice, :1 spring mounted substantially parallel to said member und secured ereto at each end, said spring being connected, betu'ecn'its ends, to said closure and tending to return the latter to any predetermined position, when the closure is moved from that position, substantially as described.

10. A niufiler provided with a member boring an orifice, a closure mounted on said member and pivotully mounted to restrict or enlarge said orifice, a spring mounted adjacent said member and s0 connected to said closure as to tend to move said closure to a predetermined position when the closnrc moved from that position and means whereby said spring may be bodily moved to thereby increase or diminish sold tendency.

In testimony whereof I allix my Signature.

FREDElllCTK KOPl-"ER, 2:. 

